1. Field of the Invention
The invention relates to a continuous casting plant including at least one continuous casting line, optionally, at least one reducing unit, at least one separation device, and one or more devices for tempering the strip, and a downstream rolling train.
2. Description of the Prior Art
The so-called CSP-plants (Compact Strip Production) provide for a continuous and significantly shorter production of hot-rolled strips. Liquid steel is poured from a ladle in a tundish and from the tundish with a pouring tube in a mold. The mold has a shape in form of a funnel that is reduced on both parallel broad sides only in a last third of its height. The mold shape corresponds to a typical contraction course of a cooled steel. The advantage of a funnel, among others, is seen in that steel solidifies substantially stress-free and trouble-free. The rapidly solidified, in this manner, thin slabs having a thickness of about 50 mm are separated by shears before they are heated to a uniform temperature of 1,500° in a conveyor-furnace. Finally, rolling in a finishing train takes place, with finished slabs having a width from 900 to 1600 mm and thickness from 0.8 to 6.53 mm. For producing very thin sheets, six or seven very powerful rolling mill stands are used. Finally, the strip travels over a long cooling line to reels which wind the strip up into a coil. With CSP-plants, a high-quality hot-rolled strip is produced with favorable profile characteristics, better surface quality, and narrow tolerances.
The European Patent EP 1 363 750 B1 discloses a method for operating a continuous casting-rolling plant including at least one slab production line and at least one rolling mill train and further at least one slab-feeding device which technically is independent from the slab production line.
During a production interval of the slab production line, the slab feeding device takes over the delivery of slabs to the rolling mill train in accordance with logistic and/or manufacturing standards up to a maximum output possible. The mentioned further slab-production line is formed as a thick-slab production line, whereby the slab feeding device of the casting-rolling plant receives the slabs from a slab storage in which the prefabricated slabs are tempered during a manufacturing process. Those are reduced in a separate break-down train to a coil-adapted thickness. The coils are fed behind the casting plant immediately to the rolling train.
U.S. Pat. No. 7,143,499 discloses a plant for producing metal sheets of strips from carbon steels and special steels. The plant has a main casting line for producing stock form one type of steel, e.g., carbon steel, and including a rolling mill train and reheating furnace, arranged upstream of the rolling mill train and which reheat the strand fed from a casting machine for casting carbon steel slabs. The plant further includes an auxiliary line for feeding steel slabs, which are produced for a different type of steel, e.g., special steels, to the rolling mill train in the main casting line. The auxiliary line is connected with a casting machine for casting special steels and includes likewise a reheating furnace for heating the slab produced in the casting machine for casting slabs from special steels. The rolling mill train program is adapted to a given material to be rolled in the rolling mill train. The slabs are transmitted from the auxiliary line to the main line by a ferry. The auxiliary line may include a break-down stand for reducing the thickness of slabs produced in the casting machine for casting slabs from special steel to the rolling thickness of slabs in the rolling mill train of the main line if the thickness of the special steel slabs is greater.
The object of the present invention is increase of production of a CSP-plant and expanding its capabilities.